Gate for die casting



. 5, 1939. N.-LESTER GATE FOR DIE CASTING Filed April '7, 1937 INVENTOR. 71022 06 eafex 94% G M f 94 ATTORNEY.

Patented Dec. 5, 1939 UNITED I STATES PATENT OFFICE GATE FOR DIE CASTING Application April 7, 1937, Serial No. 135,522

.lClaim.

The present inventionrelates to a new and improved form of construction for a gate in a die casting mold. My invention is applicable to be used in conjunction with permanent molds for the casting of metallic and non-metallic metals such as non-ferrous alloys and plastics, under pressure. I

Heretofore it has been necessary in the die casting art to provide a gate or a channel through which the molten or liquid material to be cast flows into the mold cavity, and such a gate, upon solidification of the casting, not only results in a relatively large slug of waste material which must be removed from the casting, but also required the provision of a large and extra cavity in the die blocks which form the mold so that the gate slug can be removed from the die cavity alongwith the casting. A gate or a relatively large channel leading into the die cavity and for the reception of excess casting material is of course necessary in such casting operations.

It is the general object and nature of my' 36 of gate slugs and remelting of such waste material, as well as permitting the easier and more convenient renioval of the casting and eliminating the necessity of a special gate slug cavity in the die blocks.

0 Briefly outlined, my invention consists in the provision of a gate or inlet channel leading to the die cavity together with heating means located adjacent such gate, which heating means function to maintain the residuary or excess material in the gate in a liquid state while the casting solidifies and thereby prevents such gate slug from becoming a part of the resultant casting.

To the accomplishment of the foregoing and 50 related ends, said invention then, consists of the means hereinafter fully described and particularly pointed out in the claim.

The annexed drawing and the following description set forth in detail certain structure em- 55 bodying the invention, such disclosed means conin Fig. 1; and Fig. 3 is an elevational view of the 10 face of the right hand die block shown in Fig. 1.

Now referring more particularly to the drawing, there are shown therein a die block I which is adapted to meet with a die block 2 along the parting line P. These die blocks of course are 15 mounted in a die casting machine (not shown) and supported upon the horizontal bars 3 in such a manner that the die block 2 is movable into and out of engagement with the die block I. A plu- I rality of die cavities 4 are formed in the face 'of 20 the die block I and these cavities are placed in communication with a central point by'means of the distributing channels 5 in the die block 2. The channels 5, although not technically a part of the view as Fig. 2 is taken, are nevertheless shown in dotted lines. for the purpose of more conveniently illustrating the, construction. Core pieces 6 are carried in the die block 2 and their extending ends, or left hand ends as seen in Fig. 1,- form the malepart of the die cavity 4. Ejector pins 1 are mounted in the core pieces 6, and an ejector pin 8 is also mounted in the die block 2 at the point of central convergence of the channels 5. 7 As is well understood in the art, these ejector pins function to force or eject the casting away from the face of the die block 2 as the latter is moved to open position with respect to the die block I.

A gate or inlet channel 9 is provided in the. die block I and leads to the opening 9' located 40 substantially at the central portion of the casting cavity. The other end of the gate 9 is in communication with the passage in the connector III which in turn leads from the pressure casting source of the die casting machine. The connector III has a semi-spherical end surface which fits in the corresponding convex recess II in the die block I.

The bottom walls of the gate 9 are formed by an insert I2 attached to the die block I, and this insert I2 has a central passage for the reception of a heating element such as an electrical resistance coil. In this manner the walls of the gate or inlet channel 9 are so heated as to prevent the excess material in the gate 9 from becoming solidified during the time that the material solidifies in the cavities 4. It will also be noted that the walls of the gate 9 are horizontally inclined in an upward direction toward its discharge end fl'rwhereby the excess metal in the gate 9 will tend to run back down into the connector l0 and not out toward the face of the die block I as the casting pressure is relieved and as the die blocks I and 2 are moved to'open position. 1

Other modes of applying the principleof my invention may be employed instead of the one explained, change being made as regards the structure) herein disclosed, provided the means stated by the following claim or the equivalent or such stated means be employed.

I therefore particularly point out and distinct-- ly claim as my invention:

In a casting die, the combination of separable,

die b locks forming a die cavity, a gate through one of said blocks leading to said cavity, and an insert having an outer wall constructed and arranged to lie flush with and extend across the 

